X-ray tube



April 1934. H. NICLASSEN 1,954,709

X-RAY TUBE Filed April 17. 1930 I or/veg Patented Apr. 10, 1934 PATENT OFFICE X-RAY TUBE Hans Niclassen, Berlin,

0. H. F. Muller Aktiengesellschaft,

Germany,

Germany, assignor to Hamburg,

a corporation of Germany Application April 17, 1930, Serial No. 445,067

8 Claims.

My invention relates to X-ray tubes.

X-ray tubes having metallic median portion have advantages over X-ray tubes in which the wall consists exclusively of glass in that the metallic median part provides a support for the body of the tube. While heretofore, both ends of the metal part having the glass tubes connected thereto were used for mounting the tube, metal tubes are mounted at a single point coinciding with the centre of gravity of the tube, so that the tube can be more readily moved thus facilitatingits operation by the physician.

Efforts have been made to use the said supporting system also in glass tubes, the median part of the glass tube being provided with a metallic sleeve having the supporting means for the tube attached thereto. However, tubes of this type have never been used in practice, because the construction resulted in a disruption of the wall of the glass tube.

The object of the present improvements is to provide a tube in which this objection is obviated. While in Rontgen tubes having a metallic median part the emitted electrons may without danger impinge upon the median metallic part, so that at this part a compensation of the charge takes place, a glass tube provided with an outer metallic sleeve is subject to disruption of the glass wall, because the emitted electrons charge the inner part of the glass wall, which results in a high dielectric strain of the glass wall. In my improved tube this danger is obviated by screening the space subject to the charge or the median portion of the glass wall impinged upon by the electrons. A metallic screen may be provided, for example, by conductive bodies placed within the tube, or by coating the glass wall itself with metal by cathode disintegration or by galvanic methods. The said metallic coating may be electrically connected with the outer metallic sleeve to which the supporting means is attached, so that the charge caused by the said electrons is prevented, and there is no strain of the glass wall.

For the purpose of explaining the invention an example embodying the same has been illustrated in the accompanying drawing showing a sectional elevation of the tube.

Within a glass envelope 1, which preferably embodies a cylindrical outer wall, there are an anode 2, and a cathode 3 which are supported in re-entrant portions of the envelope, extending from opposite ends of the tube. For preventing a charging of the glass within the tube I provide improvements in Germany April 19, 1929 ductive body 4 located within the tube may be i electrically connected with the metallic sleeve 5 by a wire 6.

I claim:

1. An X-ray tube comprising electrode members between which during the operation of the tube a high potential difference occurs, a glass envelope having a single walled median portion enclosing the operative parts of said members, the Wall of said envelope extending from one member to the other and serving to insulate the same, an external metallic supporting sleeve surrounding the median portion of said envelope and conductive screening means within the envelope opposite said sleeve and electrically connected thereto.

2. An X-ray tube comprising electrode members between which during the operation of the tube a high potential difierence occurs, a glass envelope enclosing the operative parts of said members, the wall of said envelope extending from one member to the other and serving to insulate the same, an external metallic supporting sleeve surrounding the median portion of said envelope and extending for only a small part of the length thereof and a conductive coating upon the inner surface of said envelope opposite said sleeve.

3. An X-ray tube comprising an envelope, electrodes arranged within and mechanically connected by the wall of the envelope, a relatively short, rigid supporting sleeve of substantial thickness surrounding and engaging the envelope wall midway the ends thereof, supporting means cooperating with said sleeve and conductive screening means within the envelope opposite said sleeve and surrounding the operative parts of the electrodes.

4. An X-ray tube comprising a glass envelope, an anode and a cathode within said envelope, a metallic supporting sleeve of substantial thickness and provided with an aperture for the -rays, said sleeve surrounding the envelope at the median portion thereof, supporting means 2 for the tube cooperating with said sleeve and a second metallic sleeve within the envelope opposite the first-mentioned sleeve and surrounding the operative parts of the anode and cathode.

5. An X-ray tube comprising a glass envelope, an anode and a cathode within said envelope, a metallic supporting sleeve of substantial thickness surrounding the envelope at the median portion thereof, supporting means for the tube cooperating with said sleeve and a second metal lic sleeve within the envelope opposite the first mentioned sleeve and extending longitudinally of the tube beyond the operative parts of the anode and cathode.

6. An electric discharge tube comprising an envelope having a single-walled substantially cylindrical median portion and re-entrant portions at the ends thereof, the substantially cylindrical portion of said envelope extending from one of said re-entrant portions to the other re-entrant portion, an anode supported by one of said reentrant portions of the envelope, a cathode supported by the other re-entrant portion, a conductive screen inside of said envelope surrounding the operative parts of said anode and said cathode and an external conducting sleeve on the outside of said envelope opposite said inside screen and conductively connected thereto.

'7. An X-ray tube comprising electrode members between which during the operation of the tube a high potential difference occurs, a glass envelope having a single-Walled median portion enclosing the operative parts of said members, the wall of said envelope extending from one member to the other and serving to insulate the same, an external metallic supporting sleeve surrounding the median portion of said envelope, said envelope extending for a considerable distance beyond both ends of said sleeve, and conductive screening means within the envelope opposite said sleeve.

8. An X-ray tube comprising a glass envelope having a single cylindrical outer wall at the median portion of the tube, spaced electrodes arranged within said envelope and inner and outer metallic sleeves adjacent the wall of said envelope at the median portion thereof, said sleeves extending longitudinally of the tube beyond the operative parts of the electrodes and said envelope extending a substantial distance.

of said sleeves.

HANS NICLASSEN.

beyond the ends 

